The day of the frogs


Each year at the beginning of Spring common hundreds frogs mate in a single pond. A closer look at one of the most spectacular breeding grounds of the Vertebrates world

By Emanuele Biggi and Francesco Tomasinelli

There is a small pool, lost in the Italian Northern Apennines, about 1500 mt above sea level. A pond where thousands common frogs (Rana temporaria) come to breed each year in the first days of Spring. Similar things also occur in other humid areas in the mountains but here, thanks to a lack of disturbance, this phenomenon takes immense proportions.
The melting snow triggers the assault of the frogs from the nearby beech forest where they passed the winter months. Into the water, still filled with snow and melting ice, they wildly mate in big numbers. Several males could grasp a single female, sometimes taking her to death by suffocation. The water is filled with eggs, so many that the frogs can crawl on them without touching the water. In a few days this gigantic orgy comes to an end, with most frogs dispersing on the shores of the lake and in small streams. Now millions of tadpoles live into the pond. They’ll have a hard life because many predators will try to forage on them, but their number will keep some of them safe, lowering the individual probability to be predated. During summer the pond will host the new generation, hundreds of small froglets will emerge from water in search of a good meal, a nice place to stay and, once again, a mate to breed.

A special thanks to Claudio Pia for his precious advices and to Sara Costa for helping on taking these pictures